When strands are manufactured or processed, they are generally, at some point, either cleaned, lubricated, or cooled with a liquid. Each of these processes can, and usually does, leave a liquid residue on the strand's surface. These residues are typically removed from the strand's surface before the strands are further processed or before they are stored. Industry practice for removing these liquid residues generally falls into one of two basic categories. The first is a mechanical wipe which mechanically removes or wipes liquids from the surface of a strand. The second method is a gaseous blast for "blowing" the residue from the surface of the strand.
Mechanical wipes have the advantage of being very efficient in removing liquid residues so long as the wipes are operated within certain narrow parameters. The surface from which the liquid is being removed must be smooth and regular and contact between the surface of the wipe and the surface being wiped must be maintained in good condition and the surface of the wipe must be configured very closely to the shape of the surface being wiped. In the manufacture of strands, including both mono-strand and bunched or twisted strands, the surfaces cannot always be counted on to be regular or smooth. Surface irregularities are not as much a problem with mono-strands as they are with bunched or twisted strands. With bunched or twisted strands, there is little regular surface for the wipe to contact. Contact with a regular surface is critical to the operation of wiping type liquid removers. The more irregular the surface being wiped, the less effective will be the wiping process. The contact surface of the wipe is also a critical consideration. The point or points where contact is made between the strand and the wipe is a point of friction. This friction will erode the wipe contact surface such that there is a loss of intimate contact between the wipe surface and the strand. This too results in a loss in the efficiency of the wiping process.
The second, or gaseous blast, type of liquid removal system is another which is found in common use in strand manufacturing and processing industries. This liquid removal system relies upon a stream or curtain of high velocity gas, usually air, to blow liquid residue from the surface of a strand. In these systems, the strand is typically passed through devices generically known as "air wipes". These devices comprise a bore through which the strand passes. Co-operating with this bore are nozzles or passageways which direct high velocity streams of air, or some other suitable gas, directly onto the surface of the moving strand. The action of this air on the strand surface is such that it blows the liquid residue from the surface of the strand.
The disadvantages of both of these typically used liquid removing systems is that they only remove a limited amount of liquid from the strands being processed. As was indicated, the mechanical wipe will eventually fail to maintain intimate contact with the strand and the result is a poor fit and an incomplete removal of the liquid from the surface. In the case of bunched or twisted strands, the system is inherently inefficient at best. In the case of the air wipe, a buildup of liquid on the advancing strand which eventually forces its way past the air wipe and remains on the surface of the strand. The surface of strand treated by an airwipe retains a fair amount of moisture thereon. The typical strand surface remains damp even after being treated. Another disadvantage of the airwipe type system is the need for pressure regulating equipment and drying filters in the air or gas lines. Pressure regulators are needed to insure that constant gas flows are directed onto the strands. Drying filters are necessary since compressed air contains unacceptable amounts of moisture and water and when directed, unfiltered, onto the advancing strands, it will actually apply a layer of moisture or liquid onto the strand.
There exists a need for a method and means that will more efficiently remove liquid residues from the surface of a moving strand. It is this need that is addressed by the present invention.